Mrs~~Kathleen Agnes (Kennedy) Cavendish, Marchioness of Hartington (February 20, 1920 – May 13, 1948) was an American socialite. She was the fourth child and second daughter of Joseph P. Kennedy, Sr. (1888–1969) and Rose Fitzgerald (1890–1995). She was a sister of future U.S. President John F. Kennedy (1917–1963) and widow of politician William J. R. Cavendish (1917–1944)  ♡❀♡✿♡❁♡✾♡✽♡❃♡❀♡  http://en.wikipedia.org/wiki/Kathleen_Cavendish,_Marchioness_of_Harti